The present invention relates to an image reading apparatus in which lights from a plurality of light emitting units are irradiated to a reading target and reflected lights are received thereby to read an image, and to a facsimile apparatus and a copying apparatus each provided with the image reading apparatus.
There is a known image reading apparatus in which a light of a color is irradiated from a light emitting unit to a document as a reading target and a reflected light thereof is received by a plurality of light receiving units thereby to read an image from the document.
Also, it is proposed regarding an image reading apparatus of this type to irradiate a light of a color from a light emitting unit to a target for testing, receive output signals from all light receiving units, and analyze the output signals, thereby to determine whether or not the light emitting unit and all the light receiving units are operating in a normal manner.